BRPI0721419B1 - METHOD ON A USER EQUIPMENT TO PROVIDE CHANNEL STATE REVIEW OF USER EQUIPMENT FOR A BASE STATION, USER EQUIPMENT, METHOD IN A BASE STATION UNDERSTANDING A SCHEDULER TO OBTAIN DECANAL STATUS STATUS OF A USER EQUIPMENT, AND, BASE STATION - Google Patents

Abstract

method on a user device, to provide channel state feedback from the user device to a base station, user device, method on a base station comprising a programmer to obtain channel state feedback from a user device, and, base station is provided channel state feedback from an eu (800) to a base station (700) as a first type of detailed channel state feedback information or a second less detailed type. initially, it is determined (403) whether the eu has received an uplink permission from the base station or not. if the eu received an uplink permission, a first type of channel state feedback information is transmitted (404) to the base station, at the authorized resource. if, however, the eu has not received an uplink permission, a second type of channel state feedback information is transmitted (405) to the base station. different types of channel state feedback information enable an eu and an associated base station to use available resources more efficiently, by requesting and providing channel state feedback information.

Description

“METHOD IN A USER'S EQUIPMENT TO PROVIDE USER EQUIPMENT CHANNEL STATE FEEDBACK TO A BASE STATION, USER EQUIPMENT, METHOD IN A BASE STATION UNDERSTANDING A SCHEDULER TO OBTAIN CHANNEL STATEMENT OF A USER EQUIPMENT, AND, BASE STATION ”TECHNICAL FIELD

[0001] The present invention relates in general to a method and arrangement for providing channel state feedback, from user equipment to a base station, and especially for making more efficient use of available resources when providing channel state feedback. channel.

FUNDAMENTALS

[0002] The recent increase in the use of mobile data and the emergence of new applications such as games, mobile TV and streaming media content, has motivated the Third Generation Partnership Project (3GPP) to work on Long Term Evolution ( LTE), in order to give 3GPP a competitive advantage over other competitive cellular technologies.

[0003] LTE has configured aggressive performance requirements that rely on physical layer technologies, such as Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Inputs, Multiple Outputs (MIMO) systems, to achieve these goals. Some of the main objectives of LTE are to minimize the complexities of the System and User Equipment (UE), to allow flexible spectrum placement in the new or existing frequency spectrum, and to enable coexistence with other 3GPP radio access technologies (RATs).

[0004] In the LTE concept defined in the ongoing 3GPP standardization work, the downlink will support fast channel-dependent programming in both time and frequency domains. a

Petition 870200033037, of 03/11/2020, p. 5/40 / 28 conventional downlink programming concept according to the prior art can be described with stages 1: 1 - 1: 4, as shown in Figure 1. A base station 100, which is referred to as a reinforced Node B , or eNodeB in LTE, communicating with an UE 101, transmits reference signals to the UE 101 in a first stage 1: 1. Reference signals can be used by the UE 101 to determine the current downlink channel quality. After determining downlink channel quality based on received reference signals, UE 101 sends one or more channel status feedback reports, which in this context are typically represented by Channel Quality Indication (CQI) reports , back to eNodeB 100 in a second 1: 2 stage. In eNodeB 100, the content of one or more CQI reports can be retrieved and used by a scheduler (not shown), to perform resource allocation. The UE 101 is informed of the resource allocation at a next 1: 3 stage which is followed by the forward link data transmission through the allocated resource, as indicated with a final 1: 4 stage.

[0005] More on this subject can be found in “3G Evolution: HSPA and LTE for Mobile Broadband” by E. Dahlman, S. Parkvall, J. Skold, P. Beming, Academic Press, 2007.

[0006] In a proposed realization for LTE, UEs will be able to transmit different types of CQI reports, such as full CQI reports, partial CQI reports and differential CQI reports. In this context, full CQI reports are defined to cover the total downlink transmission bandwidth programmed for a UE. Different full CQI reports, however, have different frequency resolution and can also be filtered and processed in different ways. In addition, different full CQI reports can be coded in a variety of alternative ways. Partial CQI reports, on the other hand, cover only a portion of the link transmission bandwidth

Petition 870200033037, of 03/11/2020, p. Descending 6/40 / 28. The covered part of a partial CQI report can be a set of contiguous resource blocks or a distributed set. Differential CQI reports can contain a coded version of the update vector relative to a previous CQI report.

[0007] Further, for CQI reports used in conjunction with different antenna configurations, such as SISO (Single Input-Single Output), MISO (Multiple Inputs, Single Output), SIMO (Single Input-Multiple Output) or MIMO (Multiple Inputs , Multiple Outputs), the transmission could also be different. For MIMO, a CQI report can include information such as, for example, transmission classification and / or pre-coding weights and / or other feedback parameters to be used by the eNodeB multiple antenna transmission scheme.

[0008] In a proposal for LTE submitted at 3GPP, the UE may have a set of rules that specify the conditions for CQI reports to be transmitted. According to this proposal, each CQI transmission trigger is associated with a specific type of CQI report, such that, when a trigger criterion is true, the UE transmits a CQI report of an associated type. This procedure is similar to how the compressed mode is parameterized in WCDMA. For the WCDMA compressed mode, each UE is provided with a transmission space configuration set (TGPS) consisting of transmission space configurations (TGP), each defining a configurable extension transmission space that is used for a purpose specific measurement method. CQI reports can be specified in a similar way, where each UE has a set of CQI report triggers (CRTS), consisting of one or more CQI report triggers (CRT) that specify when a specific type of CQI report will be transmitted.

[0009] Figure 2 illustrates a table of a CQI trigger configuration for a UE, according to the prior art described above. The table

Petition 870200033037, of 03/11/2020, p. 7/40 / 28 comprises several CQI report shots, CRT 1-n, configured for the UE. Each CRT is associated with one of the types of CQI reports, CQI A-X. When, for example, the triggering criteria specified by CRT 1 are true, a report type defined by CQI A will be transmitted from the UE to an eNodeB, as indicated in the table.

[00010] A CRT is typically expressed in terms of a logical expression that can involve one or a combination of timers, events and conditions, consisting of logical statements such as AND, OR, NOT, WHEN and / or IF. A simple periodic CQI report trigger can consist of just a periodic timer and a rule that a certain CQI report will be transmitted every time it ends. In another example scenario, a single event based CQI report trigger can be configured to establish that a certain type of CQI report will be transmitted every time a trigger event occurs, such as, for example, a pass-through event . A condition that could be included in the decision to transmit a certain CQI report or not, is, for example, if the downlink activity is above a specified limit.

[00011] CQI reports can also be transmitted in different ways. A CQI report could be transmitted on a dedicated control channel resource or on a programmed resource provided on a shared channel. CQI reports can occur at known time instances and use a known format for eNodeB, or the occurrence and format can be more dynamic. In the latter case, the MAC header typically needs to include information about how the CQI report was transmitted, or else eNodeB may have to perform blind detection in the CQI transmission format.

[00012] What types of CQI reports a UE will use, and what criteria will trigger them, are typically configured by a more layered signaling

Petition 870200033037, of 03/11/2020, p. 8/40 / 28 high, for example, RRC signaling. In addition to configuration rules, defining when and how CQI reports are to be transmitted, eNodeB also has the option of explicitly requesting CQI reports on request, typically using RRC signaling.

[00013] The LTE uplink is based on single carrier modulation and uses principles of multiple access by frequency, time and code division (FDMA, TDMA and CDMA). The LTE uplink consists of physical uplink control channels and data channels that are orthogonally multiplied in frequency. The single carrier property of the LTE uplink makes it impossible for a UE to transmit on a physical control channel, and a physical data channel in the same transmission time interval (TTI). Hence, if a UE is transmitted data on a physical data channel, the control information that needs to be sent on the same TTI must also be sent on the physical data channel. The UE will use the physical control channel to transmit control signaling only in the case where the UE has no data transmission and, therefore, is not using the physical data channel.

[00014] There are at least three types of control signaling that can be sent in the band on the physical data channel, in the case that the UE has uplink data to transmit, namely Hybrid ARQ (HARQ) ACK / NACK feedback for downlink data transmissions, programming requests and CQI reports.

[00015] The current assumption in 3GPP with a view to HARQ feedback and the programming request is that the HARQ will consist of one bit per MIMO stream, while the programming request may consist of only a single bit, indicating whether a UE has data that want to broadcast or not.

[00016] CQI reports, on the other hand, can be significantly larger. The number of bits that can be spent on the CQI report can depend on a number of different criteria such as:

Petition 870200033037, of 03/11/2020, p. 9/40 / 28 downlink transmission mode, for example, SISO or MIMO; type of downlink traffic, for example, VoIP or Web; downlink radio characteristics, for example, coherence time and / or coherence bandwidth; current uplink load and / or current downlink activity. Furthermore, while HARQ feedback and programming request signaling are vital for communication protocols to work as a whole, CQI reports can be seen more as a performance improvement feature for the downlink.

[00017] The more uplink resources are spent on CQI reports, the better link adaptation and scheduling decisions can be made, and the better downlink performance can be achieved. As for signaling in general, there is, however, a compromise between the amount of resources that are used for signaling and the amount of resources available for transmission of user plan data traffic. In the state of the art it is known that it is beneficial to adapt the CQI reporting scheme to the conditions listed above.

[00018] A weakness of the prior art CQI reporting mechanisms is, however, the lack of flexibility in how to use available resources.

[00019] In order to fully support all possible CQI schemes in all possible scenarios, it is necessary to allocate an unreasonable amount of physical resources for signaling physical control of the uplink.

[00020] Even with a limited number of schemes applied, new feedback schemes are difficult to introduce, especially if they require that the uplink physical control channels need to be redesigned.

SUMMARY

Petition 870200033037, of 03/11/2020, p. 10/40 / 28

[00021] The present invention aims to solve at least some of the problems mentioned above, providing a more efficient use of the physical uplink control channel.

[00022] The present invention relates to a method for triggering a CQI report transmission from a UE. More specifically, the invention relates to a method on a user device, UE, to provide channel state feedback from the UE to a base station, using one or two different types of information, where the second type of information is less detailed than the first type.

[00023] Initially, it is determined whether the UE has received an uplink permission for the base station or not. If the UE has received an uplink permission, a first type of channel state feedback information is transmitted to the base station on the granted resource. If, however, the UE has not received an uplink permission, a second type of channel state feedback information is transmitted instead on a dedicated resource, or no channel state feedback information is transmitted. In this way, the physical uplink control channel can be scaled more efficiently, since only less detailed channel state feedback information in a format comprising very few bits is transmitted on this channel. Such information could include, for example, the selection of a specific antenna from an antenna array. More detailed channel state feedback information in a format comprising a large number of bits is transmitted on the granted resource. Such information could comprise, for example, frequency information at the resource block level.

[00024] So, the invention limits the amount of overhead that needs to be allocated in a “dedicated” way for channel state feedback, while still allowing detailed feedback to be transmitted

Petition 870200033037, of 03/11/2020, p. 11/40 / 28 in a scheduled resource. Without the present invention, these dedicated resources would need to be scaled to process the worst case CQI report demand, including possible MIMO requirements. Furthermore, the reserved physical control channel resources would be spent if the uplink data transmitted, since the uplink control signaling would then be transmitted using the programmed resource instead, and the reserved resources would not be used. By implementing the suggested mechanism, the uplink control channel could, instead, be configured to a minimum requirement.

[00025] According to one aspect of the invention, a UE receiving a permission when it has no uplink data to transmit, sends channel state feedback, even if no other condition that normally triggers a CQI report transmission is valid. As a consequence, the base station may interpret a programmed uplink transmission that consists only of channel declaration feedback, such as a CQI report, as an implicit signaling of an empty buffer status information message and / or as an acknowledgment in the uplink permission message that was transmitted on the downlink.

[00026] In addition, by introducing the proposed channel state feedback triggering procedure, it is possible to avoid sending unnecessary CQI reports, thereby saving control channel resources. [00027] Another embodiment further comprises the step of transmitting only the channel state feedback information, if the channel state feedback trigger criteria specified for the UE are verified as valid.

[00028] According to yet another embodiment, the least detailed type of channel state feedback information is

Petition 870200033037, of 03/11/2020, p. 12/40 / 28 periodically transmitted, if the UE does not have uplink permission, while the first, more detailed, type of channel state feedback information is periodically transmitted if the UE has an uplink permission.

[00029] According to another embodiment, two alternative means for transmitting channel status feedback information of the first type are provided. According to this realization, both presence of an uplink permission and uplink data are considered. If the UE has uplink data and an uplink permission, a programmed uplink transmission will consist of both channel status feedback information and uplink data. If, however, uplink data is not present, a programmed uplink transmission will consist only of channel state feedback information. Uplink transmission programmed according to any of the described embodiments can be used as a signaling of an empty buffer status information to the base station, or as an acknowledgment of an uplink permission that was transmitted on the downlink.

[00030] According to yet another embodiment, the report to be used for transmitting the respective channel state feedback information may be dependent on the size of the received uplink permission, that is, a base station may be able to select the size of a requested channel state feedback report, varying the size of the uplink permission, and the UE will be able to recognize the size as an indication of how much information is required by the base station. In addition, such a mechanism will offer an alternative for blind detection, since the base station knows which format of channel state feedback information to expect. According to the

Petition 870200033037, of 03/11/2020, p. 13/40 / 28 suggested realization, the size of the uplink permission received on a UE is compared with a threshold, T1 channel state feedback information is prepared and transmitted in a report of a first type, having a size associated with T1 only if the uplink permission size exceeds T1. Such a comparison can also be gradually repeated for one or more limits, T2 ... Tn, where T1> T2 ...> Tn and where each limit is associated with a specific type of report. The size of the uplink permission can be set to represent an indication of the bandwidth, modulation size and / or code rate associated with the uplink permission.

[00031] Alternatively, the remaining available energy for data transmission can be included on the uplink as a condition for transmitting the channel state feedback information.

[00032] According to another aspect, a UE to provide channel state feedback from the UE to a base station is presented, comprising a determination unit to determine whether the UE has received an uplink permission from the base station or do not. The UE also comprises a transmission unit for transmitting a first type of channel state feedback information to the base station on the granted resource, if the UE has received an uplink permission, or a second type of state feedback information. channel on a dedicated resource, if no uplink permission has been received. Alternatively, no channel state feedback information is transmitted at all in the last scenario, that is, channel state feedback is only transmitted in response to an incoming uplink permission.

[00033] In another embodiment, the unit of determination can be additionally adapted to determine whether fire trigger criteria

Petition 870200033037, of 03/11/2020, p. 14/40 / 28 relevant channel state feedback specified for said UE are valid or not. According to this realization, channel state feedback information is only transmitted if the channel state feedback trigger criteria are also verified as valid.

[00034] Channel status feedback information is typically transmitted in a report generated by a generation unit.

[00035] According to yet another realization, the generation unit can be adapted to periodically generate a second type of less detailed report, if the UE does not have uplink permission, while a second type of more detailed report is, at the same time. instead, generated if the UE has an uplink permission.

[00036] According to another alternative embodiment, the unit of determination can be adapted to compare the size of a dynamic uplink permission with a T1 limit, and to generate a report associated with T1, if the size of the link permission ascending exceeds T1. The unit of determination can also be adapted to gradually repeat such a procedure for one or more limits, as described above. If a report is required for all occasions, the lower limit can be set to 0.

[00037] In one embodiment, the determination unit may also be adapted to include remaining available energy for data transmission on the uplink, as a condition for generating a channel state feedback report.

[00038] In accordance with yet another aspect, a method is provided at a base station, comprising a scheduler for obtaining channel state feedback from a UE. According to one aspect of the invention, it is the presence of downlink data at the base station that triggers the scheduler to provide an uplink permission to the UE in order to receive the downlink channel status feedback.

Petition 870200033037, of 03/11/2020, p. 15/40 / 28 required for link adaptation and / or downlink data channel dependent programming for that UE in the granted resource. So, in case the base station needs channel state feedback information, although there is no uplink transmission in progress, an uplink permission can be sent from the base station to obtain the information. If the scheduler has determined that channel state feedback is required, an uplink permission is generated, and the uplink permission is provided to the UE in order to receive channel state feedback on the granted resource.

[00039] According to another embodiment, it is also determined whether downlink data is present or not at the base station, and if this is the case, an uplink permission is generated and provided to the UE, in order to receive feedback downlink channel state status on the granted resource.

[00040] According to yet another realization, the load of the uplink is considered, determining at the base station whether the uplink load is below a limit, th, or not. If this is the case, an uplink permission is generated is provided to the UE. Otherwise, the signaling required to provide channel status feedback information is avoided in favor of traffic in progress.

[00041] An uplink permission may be provided to the UE for the purpose of receiving an uplink transmission on the granted resource, containing at least the channel state feedback. The retrieved uplink transmission can then be used by the base station to estimate the uplink channel quality for link adaptation and / or uplink data channel dependent programming from the UE. Thus, the use of both uplink proof and unscheduled CQI reports can be limited. The scheduler can then place the channel status feedback reports

Petition 870200033037, of 03/11/2020, p. 16/40 / 28 in resources where you want to prove the uplink channel. Alternatively, uplink permission can be provided to the UE for the purpose of maintaining uplink synchronization.

[00042] In accordance with yet another aspect, a base station, comprising a scheduler adapted to obtain channel state feedback from a UE is provided. The scheduler comprises a generation unit, adapted to determine whether channel state feedback is required or not and, in the event that channel state feedback is required, the generation unit is additionally adapted to generate an uplink permission on the to receive UE channel status feedback on the resource granted. The uplink permission is then transmitted by a transmitting unit, and a receiving unit is adapted to receive channel state feedback in response to the transmitted uplink permission.

[00043] According to an alternative embodiment, the generation unit is adapted to provide an uplink permission to the UE, in order to receive downlink channel status feedback required for link adaptation and / or channel dependent programming of downlink data to the UE in the granted resource, if it is verified that the base station has downlink data.

[00044] According to another embodiment, the generation unit is adapted to provide an uplink permission to the UE, if it is found that the uplink load in the UE is below a specific limit, th. The threshold is typically adapted in such a way that uplink data from other UEs will not be negatively affected.

[00045] According to yet another embodiment, the generation unit may be adapted to provide a UE with an uplink permission for the purpose of receiving an uplink transmission on the granted resource, where the uplink transmission comprises

Petition 870200033037, of 03/11/2020, p. 17/40 / 28 at least channel state feedback. The scheduler can also be adapted to use uplink transmission to estimate uplink channel quality for link adaptation and / or uplink data channel dependent programming from the UE.

[00046] The generation unit may be adapted to provide an UE with an uplink permission for the purpose of maintaining uplink synchronization. Alternatively, the generation unit can be adapted to generate a variable length uplink permission, enabling the base station to request variable size channel status feedback information.

BRIEF DESCRIPTION OF THE DRAWINGS

[00047] The present invention will now be described in more detail by means of typical realizations and with reference to the accompanying drawings, in which:

Figure 1 is a basic overview of a signaling procedure between user equipment and an eNodeB, according to the prior art.

Figure 2 is a table indicating a configuration of CQI report triggers, according to the prior art.

Figure 3 is a flowchart illustrating a procedure for providing a CQI report from a user device to an eNodeB, according to the prior art.

Figure 4a is a flow chart illustrating a procedure for selecting a CQI report on a user device, according to an achievement.

Figure 4b is a flow chart illustrating a procedure for selecting a CQI report on a user device, according to another realization.

Petition 870200033037, of 03/11/2020, p. 18/40 / 28

Figure 5 is a flowchart illustrating a procedure for selecting a CQI report on user equipment, according to yet another realization.

Figure 6 is a flowchart illustrating a procedure for selecting a CQI report on user equipment, according to another alternative realization.

Figure 7 is a block diagram, schematically illustrating an eNodeB, adapted to request a CQI report, according to any of the described accomplishments.

Figure 8 is a block diagram, schematically illustrating a UE, adapted to provide a CQI report to a base station, according to any of the described achievements.

Figure 9 is a flowchart illustrating a procedure for an eNodeB to request a CQI report from an UE, according to one embodiment.

Figure 10 is a flowchart illustrating a procedure for an eNodeB to request a CQI report from a UE, according to another embodiment.

DETAILED DESCRIPTION

[00048] Briefly described, the present invention involves a method, user equipment and a base station adapted to process channel state feedback reports in a more flexible way. More specifically, a channel state feedback procedure is provided that uses the available resources to transmit channel state feedback more efficiently. This is achieved by including uplink permission available in the channel state feedback report triggers used to determine when to send channel state feedback from a UE, i.e., a channel state feedback reporting rule is configured in the UE,

Petition 870200033037, of 03/11/2020, p. 19/40 / 28 specifying that the channel state feedback report will be based on whether the respective UE has obtained an uplink permission or not. Alternatively, available uplink permission is configured to be the only trigger, specifying which type of channel state feedback report to transmit. Using a uplink permission, either alone or in combination with other channel state feedback trigger criteria, a base station will also be able to achieve more in addition to using channel state feedback reports than is possible with solutions from prior art.

[00049] In the following exemplified embodiments, channel state feedback reports provided from the UEs will therefore be referred to as CQI reports and base stations will be referred to as enhanced LTE base stations, that is, eNodeBs. In addition, channel state feedback rules, specifying when to transmit a CQI report, which can be expressed in terms of a logical expression involving one or a combination of timers, events and / or conditions, will be referred to as CQI report triggers . It should, however, be understood that the described accomplishments may also apply to other comparable channel state feedback implementations.

[00050] Figure 3 is a simplified flowchart illustrating a procedure for providing channel state feedback in the form of CQI reports from a UE to an eNodeB, according to the prior art. In a first step 300, the criteria for when and how to provide different types of CQI reports, typically defined as specified above with reference to Figure 2, configured as CRTs by eNodeB, are provided and received by the UE. In a next step 301, a continuous verification procedure, to determine whether the CRT criteria specified by the CRTs are met, is initiated. If the criteria for a

Petition 870200033037, of 03/11/2020, p. 20/40 / 28

CRTs are verified as satisfied in step 302, a CQI report of the respective type will be transmitted by the UE, as illustrated with a final step 303. If, however, the CRT criteria are not met, the verification procedure is repeated, starting again with step 301. If there are several different types of CQI reports configured for the UE, the verification procedure will be repeated accordingly for each type of report. Obviously, such a procedure for deciding when to transmit CQI reports leaves no room for flexibility as to the use of available resources or as to what information can be retrieved from a CQI report.

[00051] Knowledge of the precise quality of the channel in eNodeB is mainly required when data is transmitted on the downlink. When there is no downlink data transmission in progress, however, there is no or very little need for detailed CQI reports. Furthermore, when the UE is receiving data on the downlink, there will typically also be transmission activity on the uplink, and then CQI reports should preferably be sent mainly when the UE is transmitting in any way on the uplink in response to transmissions from downlink, as this will minimize the amount of semi-statistically allocated CQI resources. For this reason, the CQI overhead can be reduced by defining two different CQI formats, where a first format using a larger number of bits is used in situations where the UE should transmit data on the uplink anyway, while a second format using a smaller number of bits is used for CQI transmission only. Since the transmission structure is different for the two transmission cases, having different sizes for the two CQI report formats, this procedure will not complicate the overall structure.

[00052] According to one embodiment, two different types of

Petition 870200033037, of 03/11/2020, p. 21/40 / 28 CQI reports, specified as a low resolution type, that is, an unrefined type, and a high resolution type, that is, a detailed type, respectively, are specified and the report trigger criteria CQI associated with these two types of CQI reports are configured in such a way that if a UE is found to have received an uplink permission from an eNodeB during a CRT check, the UE will transmit a detailed high-resolution CQI report using the resource granted, while an unrefined low-resolution CQI report will be transmitted on the dedicated uplink physical control channel, if no uplink permission has been received. A method for managing the provision of CQI reporting in accordance with this realization will now be described in further detail with reference to Figure 4a.

[00053] The first two steps 400 and 401 are performed in the same way as for the prior art described above, referring to Figure 3. in a subsequent step 403, however, it is determined whether or not the UE received a link permission. ascending. The presence of an uplink permission in the UE is unconditionally interpreted by the UE as an indication that a CQI report of the first type (type 1) must be transmitted to eNodeB in the granted resource. Such transmission, which can comprise both data and channel state feedback information, is transmitted in a 404 step. If, however, no uplink permission is present in the UE, a second type CQI report (type 2), comprising only channel state feedback information, it must be transmitted in a dedicated resource, as indicated in another step 405. Alternatively, the type 2 CQI report alternative can be configured to instruct the UE not to transmit any CQI report, ie , a CQI report is only transmitted to the eNodeB of an uplink permission is present in the UE.

[00054] According to another realization, which will be described with

Petition 870200033037, of 03/11/2020, p. 22/40 / 28 reference to Figure 4b, also other triggering criteria, defined as CRT criteria, are considered when determining which type of CQI report to transmit from the UE. CRT criteria can, for example, be based on the time since the last transmission of a CQI report took place and / or whether the current downlink activity exceeds a predefined limit or not.

[00055] In Figure 4b, steps 400 and 401 are equivalent to those already shown in Figures 3 and 4a. In a next step 402, however, the relevant criteria are verified. If the CRT criteria are not valid, no CQI report is transmitted, and the verification procedure is restarted in step 401. If, on the other hand, the CRT criteria are verified as valid, it is determined that an uplink permission is not present in the UE, in a next step 403. If an uplink permission is not present, an unrefined type 2 CQI report is transmitted in a 404 step, while a more detailed type 11 report is transmitted instead of it, in a another step 405, if an uplink permission is present in the UE. Also in this scenario, the type 2 reporting alternative can be configured to instruct the UE not to transmit any CQI reports.

[00056] Including uplink permission availability in CQI report triggers, has major implications for the practical use of CQI reports, since CQI reports can be useful for several additional purposes compared to what can be obtained with other state solutions of the technique. An eNodeB scheduler can, for example, authorize a specific UE resource for the purpose of estimating uplink channel, regardless of having received a programming request from the UE or not. If the UE responds to the permission by transmitting a CQI report on the granted resource, the scheduler will be provided with information on the quality of the uplink and link channel

Petition 870200033037, of 03/11/2020, p. 23/40 / 28 downward at the same time. Such a procedure can be used as a more effective alternative to channel appearance, where only a reference signal, carrying no information, is transmitted from the UE.

[00057] In the situation where a UE has an uplink permission, but no uplink data temporarily stored for transmission, a type 2 CQI report received by eNodeB implicitly indicates to eNodeB that the UE has no uplink data and, as a consequence for eNodeB, requesting empty temporary storage status information by eNodeB will be superfluous, resulting in reduced signaling.

[00058] The channel state feedback procedure described can enable the scheduler of another eNodeB, which typically consists of an uplink programming function and a downlink programming function, to effect an exchange between link capacity ascending and descending link. If the downlink scheduling function requires a CQI report to be provided, you can check with the uplink scheduling function whether the corresponding UE has an uplink permission or not. If the UE already has an uplink permission, the scheduler can wait for a CQI report to be transmitted on the granted resource. If, however, the UE does not have an uplink permission, the downlink scheduling function may require the uplink scheduling function to program the corresponding user in the near future, even if the corresponding user has not made any request for programming. If the uplink load is low, the uplink scheduling function can choose to give the user a permission exactly to transmit the CQI report that the downlink scheduling function requested. If, on the other hand, the current uplink load is high, that is, higher than a specified limit value, the

Petition 870200033037, of 03/11/2020, p. 24/40 / 28 uplink programming can prioritize uplink data transmission from other users, and then resources for CQI reporting will not be used as long as the uplink load remains high.

[00059] Channel state feedback can also be used to keep uplink users synchronized. The channel state feedback retrieved by eNodeB in response to an incoming uplink permission can be used to control the load on the uplink synchronization channel, allowing eNodeB to gain direct control of which users to keep in a synchronized state. For example, in low-load situations, the scheduler can choose to keep users in sync for a relatively long period of time, in order to provide a faster response time, once new data arrives at the UE. Then, programmed CQI reports can be used instead of synchronization tests on the uplink synchronization channel.

[00060] In situations where the UE is limited in power on the uplink, it may not be able to transmit a CQI report and data in the same TTI. For coverage reasons, it would then be beneficial to have the option of turning off the CQI report in cases where it was found that the energy left for data transmission has fallen below a threshold. Therefore, also the remaining available energy for data transmission could be included in the CQI report trigger criteria. Since CQI reports and data transmissions are multiplexed over time on the uplink, removing the CQI report from TTI will give a limited power UE more time to transmit the data symbols, and hence the energy of the data portion can be increased. ENodeB can interpret an absence of a CQI report that should have been included according to a CRT, as an indication that the dynamic power reserve in the UE is zero or below a minimum level. This option can then be used to avoid

Petition 870200033037, of 03/11/2020, p. 25/40 / 28 explicit signaling of the dynamic reserve for severely limited power UEs.

[00061] It is also possible to combine the suggested channel state feedback procedure with a rule that implicitly provides uplink permissions, for example, associating all downlink transmission to an implicitly authorized uplink resource. An authorized uplink resource can then be pre-configured in such a way that any UE that is programmed on the downlink can derive an uplink permission for a future uplink transmission. This implicit uplink permission can, for example, be based on the position of the downlink resource allocation description on the downlink scheduling control channel. Such a rule could be beneficial, since we know that when there is downlink data to transmit to a UE, HARQ feedback transmission, TCP feedback and CQI reports on the uplink will be required. In an alternative embodiment, a mark on the downlink designation could be used to indicate whether a downlink designation should be associated with an implicitly authorized uplink resource.

[00062] Also the use of DRX / DTX, that is, Discontinuous Reception / Discontinuous Transmission, in the UE can affect the procedure for providing CQI reports. An UE operating in a DRX / DTX mode will cease to produce an expected CQI report of a certain type, since it is configured to not pay attention to downlink reference symbols at all times. Then, a CQI trigger criterion can also include information regarding whether the UE is in a certain DRX / DTX mode or not. A DRX UE can, for example, transmit a CQI report screen image, based on a single observation of the downlink reference symbols, while a CQI report

Petition 870200033037, of 03/11/2020, p. 26/40 / 28 processed based on observations of downlink reference symbols from various TTIs can instead be transmitted if the UE is not in DRX mode.

[00063] A CQI reporting rule according to the claimed invention can be configured by stating that if a UE obtains an uplink permission when the UE does not have uplink data to transmit, it sends channel state feedback, such as a CQI report on the granted resource, even if no other CRT criteria that normally trigger a CQI report transmission are valid. As a consequence, eNodeB can interpret a programmed uplink transmission that consists only of channel state feedback, such as a CQI report, as an implicit signaling of an empty buffer status information message, and as an acknowledgment the uplink permission that was transmitted on the downlink.

[00064] An alternative procedure for managing provision of CQI reporting in an UE according to another realization, will now be described with reference to Figure 5. According to this realization, also the presence or absence of uplink data in the UE is considered and two different type 1 CQI reports, that is, detailed reports are introduced, namely a full type 1 CQI report, comprising only channel status feedback information, and a combined type 1 CQI report, comprising a combination of data from uplink and channel status feedback information.

[00065] Similar to the previous realization, this realization also begins with the configuration of a CRTS of a UE, as illustrated with a first step 500, followed by the initiation of a procedure to continuously check the CRTs specified by the CRTS in a next step 501, a one-step CRT check

Petition 870200033037, of 03/11/2020, p. 27/40 / 28

502 and an uplink permission in a subsequent step 503. Similar to the previous realization, no uplink permission in the UE results in the transmission of a type 2 CQI report in a step 504. If, however, a link permission uplink is found present in step 503, it is determined whether uplink data is present in the UE in a next step 505. Depending on whether the uplink data is present in the UE, a full or combined type 1 CQI report will be chosen for transmission of channel status feedback information. Consequently, uplink data will not result in the transmission of a full type 1 CQI report in one step 506. Such a detailed report can be configured to contain something, for example, from 10% of the channel quality information, leaving the remaining empty space, up to 100% of the channel quality information. If uplink data is present instead, a combined type 1 CQI report will be transmitted, as illustrated with another step 507. Once a report has been provided from the UE, the CRT verification procedure is repeated, starting with step 501. If eNodeB provides the UE with an uplink permission according to the described implementation, it will not, however, know whether to expect a type 1 CQI report or a type 2 CQI report, since it does not knows whether the UE has uplink data or not. ENodeB will therefore have to perform blind detection to determine whether a type 1 CQI report is a full or combined version.

[00066] The introduction of an uplink permission of a dynamic size can enable eNodeB to implicitly know the transmission format of received channel quality information and then provide a powerful alternative for blind detection. The use of such a dynamic uplink permission will now be illustrated in yet another embodiment, with reference to Figure 6. Also, in Figure 6, the steps

Petition 870200033037, of 03/11/2020, p. Initial 28/40 / 28, namely Steps 600-604 are basically performing the same procedures as steps 500-504 in Figure 5, where a CQI type 2 report is transmitted on a dedicated channel in step 604, if no uplink permissions is present in the UE. If an uplink permission is present in the UE, the size of the uplink permission will be considered in step 605. In step 605, it is determined that the size of that uplink permission exceeds a first limit T1. If this is the case, a CQI type 1 report, having a specific size, size 1, associated with the comparison step, is transmitted to eNodeB in a step 606. If, however, the size of the uplink permission is less than T1 , the procedure can be repeated, where the uplink permission is gradually compared to smaller limits, T2 ... Tn where T1> T2> ...> Tn, until a match is found, that is, the permission size uplink is greater than a threshold, and a CQI report corresponding to the respective comparison step is transmitted. A final comparison is illustrated with step 607, which results in the transmission of a type 1 CQI report of size n or no report at all. The lower limit, Tn can have a small amount or even be set to 0 if a CQI report is required to be transmitted on each occasion, when the CTR criteria have been found to be valid.

[00067] A simplified block diagram of a base station, exemplified as an eNodeB, adapted to operate in accordance with at least the achievements described above, will now be described with reference to Figure 7. It should be understood that, for the sake of simplicity, units that are not necessary for understanding the claimed invention have been omitted. It should also be understood that all units mentioned in this document must be interpreted as exemplified logic units, which can be implemented as simple units in

Petition 870200033037, of 03/11/2020, p. 29/40 / 28 combination with other units in any number of possible ways. [00068] eNodeB comprises a scheduler 701, adapted to manage programming between eNodeB and one or more UEs, represented here by UE 800. Scheduler 701, which typically includes separate uplink and downlink programming functions (not shown), comprises a generation unit 703, adapted to determine whether channel status feedback information is required or not according to predetermined rules configured for scheduler 701, and to generate an uplink permission to be transmitted to the UE 800 when it is verified that the channel status feedback information is required. An uplink permission generated by scheduler 701, is transmitted to the respective UE, via transmission unit 704 of a transceiver 705, and channel state feedback, which can be transmitted to eNodeB 700 in response to the uplink permission, is received by a receiving unit 706 of the transceiver unit 705. Also, rules for how to interpret the information retrieved from the channel state feedback, the absence of an expected channel state feedback, will be specified in the configuration of a scheduler. [00069] Also, a UE operating in accordance with at least the realization described above, will require modifications. A simplified block diagram of a UE, according to one embodiment, will now be described with reference to Figure 8. Also in this figure, units and functions not necessary for understanding the claimed invention, have been omitted. The UE 800 communicating with an eNodeB 700, comprises a generation unit 801 to generate a CQI report when the specified criteria are verified as valid, according to any of the achievements described above. The generation unit 801 additionally comprises a determination unit 802, adapted to determine whether the respective CRT criterion is met or not, and then whether the respective CQI report is to be transmitted

Petition 870200033037, of 03/11/2020, p. 30/40 / 28 or not. Obviously, the determination unit 802 is configured to determine whether an uplink permission has been received by the receiving unit 804 of a transceiver unit 805 of the UE 800 and is present in the UE or not. The determination unit 802 can also determine whether the UE has uplink data to transmit or not. In addition, the determination unit may take the size of an uplink permission received into consideration when determining which version of the channel state feedback information to transmit. The CQI report triggering criteria, specified for the UE in one or more 806 CRTs, are stored within or in association with the 801 generation unit. Once the availability of an uplink permission and, if applicable, the validity of the remaining CRT criteria has been determined by the unit of determination 802, a CQI report is generated by the generation unit 801. The chosen CQI report is then transmitted to the eNodeB 700 via transmission unit 807 of the transceiver unit 805.

[00070] The steps of operating an eNodeB according to one realization will now be described with reference to Figure 9, where programming is activated in a first step 900. When it is determined by the eNodeB scheduler that a CQI report is required in a next step 901, the scheduler generates an uplink permission in step 904, and transmits an uplink permission to the respective UE in a final step 905. The schedule then proceeds accordingly, where the CQI report is awaited. Alternatively, step 901 can be represented by checking whether the downlink data is present or not, that is, whether downlink data for the respective UE is present in eNodeB, an uplink permission is generated in step 904 and transmitted in step 905, while no UL permission is transmitted otherwise.

[00071] An alternative realization of an eNodeB configuration is

Petition 870200033037, of 03/11/2020, p. 31/40 / 28 described with reference to Figure 10, where the first stage 900 and the final stages 904 and 905 are the same as described in the previous realization. In step 902, it is determined whether the downlink data is present or not. If downlink data is present, eNodeB's uplink load is compared to a limit, th, in a next step 903, and if the uplink load is verified to be below that limit, an uplink permission is generated in step 904, and transmitted in step 905. If, however, the uplink load exceeds the limit, the present load is considered too high to initiate channel state feedback transmission and then no uplink request has permission to be broadcast on that occasion.

[00072] To conclude, with more efficient control channel processing, the total available resources of a network can be used more efficiently, resulting in an improved network capacity.

[00073] Although the invention has been described in relation to the concept of LTE, any system that applies channel state feedback reporting such as CQI reporting, for example, and programmed uplink, such as, for example, WCDMA, could be applied with improved uplink. The invention is therefore not limited to the described embodiments, but is intended to cover various modifications within the scope of the appended claims.

Claims (31)

1. Method on user equipment, UE (800), to provide channel state feedback from user equipment to a base station (700), characterized by the fact that it comprises the steps of: - determining (403) whether the UE has received an uplink permission from the base station; - transmitting (404) a first type of channel state feedback information to the base station on a granted resource, in case the UE has received an uplink permission; and, - transmitting (405) a second type of channel status feedback information in a dedicated resource in the case of the absence of an uplink permission by the UE, where the second type of channel status feedback information is transmitted in a format comprising fewer bits than a format of the first type. 2. Method according to claim 1, characterized in that it additionally comprises the step of determining (402) whether the channel state feedback trigger criterion specified for the UE is valid and where the respective status state feedback information is valid. channel is transmitted (404, 405) only if the channel state feedback trigger criterion is valid. Method according to either of claims 1 or 2, characterized by the fact that, if the UE has no uplink permission, the second, a less detailed type of channel state feedback information is periodically transmitted, while the first more detailed type of channel state feedback information is periodically transmitted if the UE has an uplink permission. Method according to either of claims 1 or 2, characterized in that it additionally comprises the step of determining whether the Petition 870200033037, of 03/11/2020, p. 33/40 2/7 UE has uplink data (505) and if the UE has uplink data and an uplink permission, a programmed uplink transmission (507) will consist of both channel status feedback information and uplink data. Method according to either of claims 1 or 2, characterized in that it additionally comprises the step of determining whether the UE has uplink data and an uplink permission, but is missing uplink data and, a programmed uplink transmission (506) will consist only of channel state feedback information. 6. Method according to claim 5, characterized by the fact that the programmed uplink transmission is used as a signaling of an empty buffer status information to the base station. 7. Method according to claim 5, characterized by the fact that the programmed uplink transmission is used as an acknowledgment of the uplink permission that was transmitted on the downlink. Method according to any one of claims 1 to 3, characterized in that the type of report to be used for transmitting the respective channel state feedback information is dependent on the size of the received uplink permission. 9. Method according to claim 8, characterized in that it additionally comprises the step of comparing the size of the uplink permission with a limit (605), T1, and where the channel status feedback information is transmitted in a report of the first type (606) of a size associated with T1, if the uplink permission size exceeds T1. 10. Method according to claim 9, characterized by the Petition 870200033037, of 03/11/2020, p. 34/40 3/7 the fact that if the size does not exceed T1, the comparison is gradually repeated for one or more limits (607), T2 ... Tn, where T1> T2 ...> Tn and where a match results in the transmission of a first type of channel state feedback information report of an associated size (608). Method according to any one of claims 1 to 10, characterized in that the size of the uplink permission is an indication of the bandwidth, modulation size and / or code rate associated with the uplink permission. Method according to any one of claims 1 to 11, characterized in that the remaining available energy for data transmission is included in the uplink as a condition for transmitting the channel state feedback information. 13. User equipment, UE (800), to provide channel state feedback from the UE to a base station (700), characterized by: - a determination unit (802) for determining whether the UE has received an uplink permission from the base station; and, - a transmission unit (807) for transmitting a first type of channel state feedback information to the base station on a resource granted in case the UE has received an uplink permission, or a second type of feedback information from channel state in a dedicated resource in the event of the UE not receiving an uplink permission, where the second type of channel state feedback information is transmitted in a format comprising fewer bits than a format of the first type. User equipment (800) according to claim 13, characterized in that the determination unit is additionally adapted to determine whether the relevant channel state feedback trigger criterion specified for the UE is valid, and where the transmission unit is adapted to transmit status feedback information only Petition 870200033037, of 03/11/2020, p. 35/40 4/7 channel if the channel state feedback trigger criterion is also valid. User equipment (800) according to either of claims 13 or 14, characterized in that the channel status feedback information is transmitted in a report generated by a generation unit (801). 16. User equipment (800) according to claim 15, characterized by the fact that the generation unit is updated to periodically generate a second type of less detailed report in case the UE has no uplink permission and a second more detailed type of report in case the UE has an uplink permission. 17. User equipment (800) according to any one of claims 13 to 16, characterized in that the determination unit is adapted to compare the size of the uplink permission with a limit, T1, and where the unit of uplink generation is adapted to generate a report associated with T1, if the size exceeds T1. 18. User equipment (800) according to claim 17, characterized in that, if the size does not exceed T1, the determination unit is additionally adapted to gradually repeat the comparison procedure for one or more limits, T2. .. Tn, where T1> T2 ...> Tn, and where the generation unit is adapted to transmit an associated size report if a comparison matches. 19. User equipment (800) according to any of claims 13 to 18, characterized in that the unit of determination is adapted to include remaining available energy for data transmission on the uplink as a condition for generating the report. 20. Method at a base station (700) comprising a scheduler to obtain channel state feedback from Petition 870200033037, of 03/11/2020, p. 36/40 5/7 user (800), characterized by understanding the steps of: - determine (901) whether channel state feedback is required; - generate (904) an uplink permission in case the channel state feedback is required; - provide (905) an uplink permission generated to the UE, in order to receive channel status feedback information on a granted resource; - receiving a first type of channel status feedback information on the resource granted when the uplink permission is transmitted to the UE; and, - receiving a second type of channel state feedback information in a dedicated resource when in the absence of transmission of the uplink permission to the UE, where the second type of channel state feedback information is transmitted in a format comprising less bits than the format of the first type. 21. Method according to claim 20, characterized by the fact that the determination step further comprises determining whether downlink data is present at the base station and if downlink data is present, generating and providing an uplink permission for the UE, in the sense of receiving downlink channel status feedback on the granted resource. 22. Method according to claim 21, characterized in that the determination step further comprises determining (903) whether the uplink load is below a limit, th, and in the event that the uplink load is below the limit the limit, generate and provide an uplink permission for the UE. 23. The method of claim 20, characterized by the Petition 870200033037, of 03/11/2020, p. 37/40 6/7 the fact that an uplink permission is provided to the UE for the purpose of receiving an uplink transmission on the granted resource, containing at least channel state feedback, and where the uplink transmission from the UE is used to estimate uplink channel quality for link adaptation and / or uplink data channel dependent programming from the UE. 24. The method of claim 20, characterized by the fact that an uplink permission is provided to the UE for the purpose of maintaining uplink synchronization. 25. Method according to any one of claims 20 to 24, characterized in that the size of the uplink permission is variable. 26. Base station (700) comprising a scheduler (701) to obtain channel status feedback from a user equipment, UE (800), characterized by: - a generation unit (703) adapted to determine whether channel state feedback is required and to generate an uplink permission to receive channel status feedback information from the UE on a granted resource, in the case of information from channel state feedback is required; - a transmission unit (704) adapted to transmit the uplink permission to the UE; and - a receiving unit (706) adapted to receive a first type of channel state feedback information on the resource granted in response to the uplink permission transmitted to the UE, wherein a second type of channel state feedback information is received in a dedicated resource when in the absence of transmission of the uplink permission to the UE, where the second type of Petition 870200033037, of 03/11/2020, p. 38/40 7/7 channel is transmitted in a format comprising fewer bits than the format of the first type. 27. Base station according to claim 26, characterized in that the generation unit is additionally adapted to provide an uplink permission to the UE, in order to receive downlink channel status feedback required for link adaptation and / or downlink data channel dependent programming for the UE on the granted resource, if the base station has downlink data. 28. Base station according to claim 27, characterized by the fact that the generation unit is additionally adapted to provide an uplink permission to the UE, in case the uplink load is also below a limit, th, of such that uplink data from other UEs will not be negatively affected. 29. Base station according to claim 27, characterized by the fact that the generation unit is additionally adapted to provide an uplink permission to the UE, in order to receive an uplink transmission on the granted resource, containing at least feedback channel status, and the scheduler is adapted to use uplink transmission to estimate uplink channel quality for link adaptation and / or channel-dependent programming of uplink data from the UE. 30. Base station according to claim 27, characterized by the fact that the generation unit is adapted to provide an UE with an uplink permission for the purpose of maintaining uplink synchronization. 31. Base station according to any one of claims 26 to 30, characterized in that the generation unit is adapted to generate an uplink permission of varying size.